https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99068
--- Comment #9 from Brian Grayson ---
If I understand correctly, you're saying that it is sometimes preferred for gcc
to avoid update form, but even when the load and addi are next to each other
it's possible to use update form, like in the
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99068
--- Comment #8 from Segher Boessenkool ---
Using update form instructions constrains register allocation and scheduling.
It is *not* always a good idea.
That is one of the reasons why we currently use update form instructions only
when insns
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99068
--- Comment #7 from Brian Grayson ---
A single lhau instruction is better than two instructions (lha + addi) for many
reasons. Are there reasons that you feel a two-instruction sequence of lha+addi
is *superior* to just an lhau?
On all PowerPC
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99068
--- Comment #6 from Segher Boessenkool ---
(In reply to Brian Grayson from comment #4)
> (In reply to Segher Boessenkool from comment #3)
> > Then you get
> >
> > addi 9,9,-2
> > lhau 10,2(9)
> > addi 9,9,2
> >
> > which is worse than just
> >
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99068
Segher Boessenkool changed:
What|Removed |Added
Status|UNCONFIRMED |RESOLVED
Resolution|---
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99068
Brian Grayson changed:
What|Removed |Added
Resolution|INVALID |---
Status|RESOLVED
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99068
Segher Boessenkool changed:
What|Removed |Added
Status|UNCONFIRMED |RESOLVED
Resolution|---
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99068
Brian Grayson changed:
What|Removed |Added
Resolution|INVALID |---
Status|RESOLVED
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99068
Segher Boessenkool changed:
What|Removed |Added
Status|UNCONFIRMED |RESOLVED
Resolution|---
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99068
Andrew Pinski changed:
What|Removed |Added
Severity|normal |enhancement
Component|target
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